VALENCE, France — After most of the other top sprinters at the Tour de France succumbed in the Alps, Peter Sagan was in prime position to dominate Friday’s flat finish.

Cycling’s world champion did not disappoint, timing his move to reach maximum speed as he swung past two challengers to claim Stage 13 by a wheel length and take his third win of this race. Seconds after Sagan reasserted his status as the most feared finisher left on the Tour, overall leader Geraint Thomas safely crossed in the pack along with teammate — and nearest challenger — Chris Froome.

Behind about 20 riders with a kilometer to go, Sagan charged to overtake runner-up Alexander Kristoff and Arnaud Demare, who finished third, at the finish line.

Sagan’s 11th career win at the world’s biggest bike race came after he was the fastest to the line in bunch sprints on Stages 2 and 5. This time, Sagan was racing against a field of sprinters greatly depleted by three grueling days in the mountains.

Fernando Gaviria and Dylan Groenewegen, who both won two stages on this Tour, along with Andre Greipel all abandoned the race on Thursday, while 30-stage winner Mark Cavendish and Marcel Kittel failed to make the time cut on Wednesday. Sagan said their absence made sprinting “messy.”

“It’s changed,” he said. “Everybody wants to do a sprint now. It’s pretty messy.” Facing no attacks on the flat stage, Thomas had no trouble maintaining his advantage of 1 minute, 39 seconds over defending champion Froome.

Tom Dumoulin stayed third overall at 1:50 behind. Primoz Roglic was fourth at 2:46, and Romain Bardet was fifth at 3:07 back. After overzealous fans marred Thomas’ win on Thursday atop the Alpe d’Huez, the otherwise complete calm of Friday’s leg was briefly disturbed by a man on the roadside who tossed a smoke bomb into the center of the peloton as it passed by with 16 kilometers left. Thomas said he didn’t see the smoke bomb which, besides spitting out yellow fumes, appeared to do no harm.

As for the jeers directed toward him and Froome by fans skeptical of Froome’s clearance from doping allegations days before the start of the Tour, he said it was part of being in the spotlight. “I would rather be on the podium and be booed than be on the bus and have everyone cheering me,” Thomas said.

Thomas did ask for fans to not interfere in the race after Froome was slapped on the back going up Alpe d’Huez and contender Vincenzo Nibali was forced to quit after he broke a vertebra when knocked to the ground by a police motorbike tasked with keeping back the crowd.

The 169.5-kilometer (105-mile) leg starting from Bourg d’Oisans at the foot of the Alpe d’Huez delayed the resolution to the burning question of this race: Is Thomas really Sky’s top option while Froome seeks a fifth Tour title?

Thomas has said that although he would work to support Froome, he is not going to intentionally lose time. But with Thomas so far proving to be the stronger rider even in the mountains where Froome normally makes his mark, their team appears ready to let the road decide.

“We’ve got two cards to play and it’s good for our strategy,” Sky sports director Nicolas Portal said before Friday’s stage. “Who knows how long (Geraint) can hold this top level? Same for Froomey. The most important thing is the group is strong and we have the best position.”

Saturday’s Stage 14 is a hilly 188-kilometer trek from Saint-Paul-Trois-Chateaux to Mende as the race makes its way to the Pyrenees Mountains.

And Froome seems eager for the action to return. “Tomorrow we can see some good battles between the favorites,” Froome said. ___ Associated Press writers Andrew Dampf and Ciaran Fahey contributed ___